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Fluid Dynamics & Materials Processing 2024年第8期20卷 1773-1784页

作者： yu Wang Mengyang Ma Yong long Qingxiang Zhao Zhifei Cheng State Key Laboratory of Bridge Intelligent and Green Construction China Railway Major Bridge Engineering Group Co.Ltd.Wuhan430034China China Railway Bridge Science Research Institute. Ltd.Wuhan430034China

Shrinkage-induced cracking is a common issue in concrete structures,where the formation of cracks not only affects the aesthetic appearance of concrete but also potentially reduces its durability and *** this study,the effect of ceramsite sand addition on the properties of a ternary system of cement-ground granulated blast furnace slag(GGBFS)-phosphogypsum(PG)is *** particular,the fluidity,rheology,hydration heat,compressive strength,autogenous shrinkage,and drying shrinkage of the considered mortar specimens are *** results indicate that an increase in PG content leads to a decrease in fluidity,higher viscosity,lower exothermic peak,and lower compressive ***,the shrinkage of the mortar specimens is effectively *** incorporation of internal curing water from ceramsite sand improves fluidity,decreases both yield stress and viscosity,enhances the degree of hydration,and induces mortar ***,the inferior mechanical properties of the ceramsite sand generally produce a decrease in the compressive strength.

关键词： Phosphogypsum ceramsite sand internal curing mechanical property shrinkage

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竞技体育犯罪研究的回顾与展望

体育学刊 2010年第12期17卷 40-44页

作者：黄立龙玉梅华南师范大学法学院广东广州510006

在研究竞技体育犯罪时,应明确竞技体育犯罪与刑法中普通犯罪的区别;将黑哨假球现象纳入《体育法》,并与《刑法》有效衔接;区别体育博彩和赌博,依据《刑法》打击赌球行为;在我国的反兴奋剂法律体系中强化和细化刑事法律制约机制;应建立... 详细信息

在研究竞技体育犯罪时,应明确竞技体育犯罪与刑法中普通犯罪的区别;将黑哨假球现象纳入《体育法》,并与《刑法》有效衔接;区别体育博彩和赌博,依据《刑法》打击赌球行为;在我国的反兴奋剂法律体系中强化和细化刑事法律制约机制;应建立犯罪控制与预防机制对付观众赛场暴力;应协调行业法规与刑事法律对付运动员的赛场暴力;对违规取得竞赛资格、体育经纪行为越轨等可能涉及犯罪的问题展开进一步研究。

关键词：体育法学竞技体育犯罪赌球兴奋剂赛场暴力

Micro defects formation and dynamic response analysis of steel plate of quasi-cracking area subjected to explosive load

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Defence Technology（防务技术） 2024年第1期31卷 580-593页

作者： Zheng-qing Zhou Ze-chen Du Xiao Wang Hui-ling Jiang Qiang Zhou yu-long Zhang yu-zhe Liu Pei-ze Zhang Research Institute of Macro-Safety Science University of Science and TechnologyBeijing100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China School of Mechanical Engineering Nantong UniversityNantong226019China China North Industry Advanced Technology Generalization Institute Beijing100089China China Academy of Ordnance Science China

As the protective component,steel plate had attracted extensive attention because of frequently threats of explosive *** this paper,the evolution of microstructure and the mechanism of damage in the quasi-cracking area of steel plate subjected to explosive load were discussed and the relationships between micro defects and dynamic mechanical response were *** the explosion experiment,five observation points were selected equidistant from the quasi-cracking area of the section of the steel plate along the thickness direction,and the characteristics of micro defects at the observation points were analyzed by optical microscope(OM),scanning electron microscope(SEM) and electron backscattered diffraction(EBSD).The observation result shows that many slip bands(SBs) appeared,and the grain orientation changed obviously in the steel plate,the two were the main damage types of micro *** addition,cracks,peeling pits,grooves and other lager micro defects were appeared in the lower area of the *** stress parameters of the observation points were obtained through an effective numerical *** mechanism of damage generation and crack propagation in the quasicracking area were clarified by comparing the specific impulse of each observation point with the corresponding micro *** result shows that the generation and expansion of micro defects are related to the stress area(*** upper compression area,the neutral plane area,and the lower tension area).The micro defects gather and expand at the grain boundary,and will become macroscopic damage under the continuous action of tensile ***,the micro defects at the midpoint of the section of the steel plate in the direction away from the explosion center(*** horizontal direction) were also *** was found that the specific impulse at these positions were much smaller than that in the thickness direction,the micro defects were only SBs and a few micro cracks,and the those decrea

关键词： Explosive load Quasi-cracking area Micro defects Steel plate Dynamic response Numerical simulation

Recovering rare earths,lithium and fluorine from rare earth molten salt electrolytic slag using sub-molten salt method

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Journal of Rare Earths 2024年第9期42卷 1774-1781,I0005页

作者： Delong Yang Mingming yu yusufujiang Mubula Weiquan yuan Zheyu Huang Bo Lin Guangjun mei Tingsheng Qiu School of Resources and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou341000China Jiangxi Key Laboratory of Mining Engineering Jiangxi University of Science and TechnologyGanzhou341000China School of Resources and Environmental Engineering Wuhan University of TechnologyWuhan430070China Gannan Institute of Science and Technology Ganzhou341000China

Viewing the problem of high ene rgy consumption in the process of recovering rare earths from rare earth molten salt electrolysis slag,an environmentally friendly and low carbon process by sub-molten salt decomposition was *** thermodynamic analysis of sub-molten salt reaction indicates that the recovery of rare earths from the slag using sub-molten salt medium is thermodynamically *** this process,the rare earth fluoride and lithium in the slag are almost transformed into rare earth hydroxide,sodium fluoride and lithium hydroxide,fluorine and lithium are transferred into the washing solution,and the rare earths in the residues can be leached into solution by acid *** the optimum reaction conditions of reaction temperature 200℃,reaction time 3 h,NaOH initial concentration 80%,NaOH-Slag mass ratio 3:1,the leaching efficiency of rare earths,fluorine and lithium can reach to 99.05%,98.23% and 99.22%.After evaporation,the fluorine and lithium in the washing solution can be obtained in the forms of sodium fluoride and lithium fluoride,the recovery efficiency reach 95.5%and 92.8%,*** RE oxides(99.53%) can be obtained from the leaching solution after precipitation and roasting.

关键词： Rare earth electrolysis slag Sub-molten salt Green extraction Fluorine Lithium Recovery

Effect of Sc on Al_(3)Fe phase and mechanical properties of as-cast AA5052 aluminum alloy

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China Foundry 2024年第3期21卷 257-264页

作者： Yang Li Qing yu Feng-feng Chen Jia-wen He Hong-mei Yang Meng-nie Li Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

The AA5052 aluminum alloy is widely used in automobile and aerospace manufacturing,and with the development of light-weight alloys,it is required that these materials exhibit better mechanical *** studies have demonstrated that the addition of Sc to aluminum alloys can improve both the microstructure and properties of the *** this study,the effect of Sc on the Fe-rich phase and properties of the AA5052 aluminum alloy was studied by adding 0%,0.05%,0.2%,and 0.3%*** results show that with the increase of Sc,the coarse needle-like Fe-rich phase gradually transforms into Chinese-script and then nearly spherical particles,reduce the size of Fe-rich phase,and refine the grain with increase of high angle grain boundaries(HAGBs).These microstructure changes enhance the strength of the AA5052 alloy through Sc *** ductility of the alloy is obviously improved because the addition of a lower amount of Sc changes the morphology of Fe-rich phase from needle-like into a Chinese-script,and it is subsequently reduced as a result of significant increase in HAGBs with increasing Sc content.

关键词： AA5052 aluminum alloy Al3Fe phase mechanical properties grain boundary

Migration mechanism of atrazine in the simulated lake icing process at different freezing temperatures based on density function theory

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Journal of Environmental Sciences 2024年第10期144卷 45-54页

作者： Yan Zhang Hao Lin Aixin yu Xiaozhuang Wang yucan Liu Tongshuai Liu Chen Zhao Rui mei School of Civil Engineering Yantai UniversityYantai 264005China

Atrazine causes concern due to its resistant to biodegradation and could be accumulated in aquatic organisms,causing pollution in *** study measured the concentration of atrazine in ice and the water under ice through a simulated icing experiment and calculated the distribution coefficient K to characterize its migration ability in the freezing ***,density functional theory(DFT)calculations were employed to expatiate the migration law of atrazine during icing *** to the results,it could release more energy into the environment when atrazine staying in water phase(-15.077 kcal/mol)than staying in ice phase(-14.388 kcal/mol),therefore it was beneficial for the migration of atrazine from ice to *** explains that during the freezing process,the concentration of atrazine in the ice was lower than that in the *** calculations indicated thatwhen the temperature decreases from268 to 248 K,the internal energy contribution of the compound of atrazine and ice molecule(water cluster)decreases at the same vibrational frequency,resulting in an increase in the free energy difference of the compound from-167.946 to-165.390 kcal/*** demonstrated the diminished migratory capacity of *** study revealed the environmental behavior of atrazine during lake freezing,which was beneficial for the management of atrazine and other pollutants during freezing and environmental protection.

关键词： Density functional theory(DFT) Icing process Atrazine Migration behavior Free energy

A Simple-Prepared and Multi-Reusable Adhesive Based on Epoxy Vitrimer

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Chinese Journal of Polymer Science 2024年第10期42卷 1589-1594,I0015页

作者： yu-Ting Wang Huan Liang Yen Wei Jian-long Wang Xiang-Ming He Yang Yang Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084China The Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing100084China

Adhesives play an important role in modern society's production and daily *** robust and sustainable adhesives remains a great *** we report a sustainable epoxy-vitrimer adhesive with high adhesive strength(about 10 MPa)and reusability(82%strength after 3 times).This adhesive can be fabricated from commercially available products through a straightforward hot-pressing method without the need of *** adhesive process is also simple,requiring only 30 min at 180℃.In addition,the vitrimer adhesive has the advantages of both erasability for reuse and excellent water *** work provides a facile strategy to fabricate high-strength adhesive that ensures reusability,recyclability,low cost of raw materials,and simple processing ***,it expands the range of potential applications for epoxy vitrimers.

关键词： Epoxy Vitrimer Adhesive Reusable Sustainable

Exosomes from umbilical cord mesenchymal stromal cells promote the collagen production of fibroblasts from pelvic organ prolapse

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World Journal of Stem Cells 2024年第6期16卷 708-727页

作者： Lei-mei Xu Xin-Xin yu Ning Zhang Yi-Song Chen Department of Gynecology Obstetrics and Gynecology Hospital of Fudan UniversityShanghai 200011China Department of Gynecology Shanghai Key Laboratory of Female Reproductive Endocrine-related DiseasesShanghai 200011China

BACKGROUND Pelvic organ prolapse(POP)involves pelvic organ herniation into the vagina due to pelvic floor tissue laxity,and vaginal structure is an essential *** POP,the vaginal walls exhibit abnormal collagen distribution and decreased fibroblast levels and *** intricate etiology of POP and the prohibition of trans-vaginal meshes in pelvic reconstruction surgery present challenges in targeted therapy *** umbilical cord mesenchymal stromal cells(hucMSCs)present limitations,but their exosomes(hucMSC-Exo)are promising therapeutic tools for promoting fibroblast proliferation and extracellular matrix *** inflammation in POP group fibroblasts,stimulated primary fibroblast growth,and elevated collagen I(Col1)production in ***-throughput RNA-seq of fibroblasts treated with hucMSC-Exo and miRNA sequencing of hucMSC-Exo revealed that abundant exosomal miRNAs downregulated matrix metalloproteinase 11(MMP11)*** HucMSC-Exo normalized the growth and function of primary fibroblasts from patients with POP by promoting cell growth and Col1 expression in *** miRNAs in hucMSC-Exo targeted and downregulated MMP11 ***-Exo-based therapy may be ideal for safely and effectively treating POP.

关键词： Pelvic organ prolapse Exosomes Fibroblasts Human umbilical cord mesenchymal stromal cells Extracellular matrix Collagen I

3D-printed self-healing,biodegradable materials and their applications

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Frontiers of Mechanical Engineering 2024年第3期19卷 1-22页

作者： yu LI Guangmeng MA Fawei GUO Chunyi LUO Han WU Xin LUO MingtaoZHANG Chenyun WANG Qingxin JIN yu long School of Mechanical Engineering Guangxi UniversityNanning 530004China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi UniversityNanning 530004China Institute of Laser Intelligent Manufacturing and Precision Processing School of Mechanical EngineeringGuangxi UniversityNanning 530004China College of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China State Key Laboratory of Precision Manufacturing for Extreme Service Performance Central South UniversityChangsha 410083China

3D printing is a versatile technology capable of rapidly fabricating intricate geometric structures and enhancing the performance of flexible devices in comparison to conventional fabrication ***,3D-printed devices are susceptible to failure as a result of minuscule structural impairments,thereby impacting their overall *** utilization of self-healing,biodegradable materials in 3D printing holds immense potential for increasing the longevity and safety of devices,thereby expanding the application prospects for such ***,enhancing the self-repairing capability of devices and refining the 3D printing performance of self-healing materials are still considerable challenges that need to be addressed to achieve optimal *** paper reviews recent developments in the field of advancements in 3D printing using self-healing and biodegradable ***,it investigates self-healing and biodegradable materials that are compatible with 3D printing techniques,discussing their printability,material properties,and factors that influence print ***,it explores practical applications of selfhealing and biodegradable 3D printing technology in ***,it critically offers practical perspectives on this topic.

关键词： 3D printing self-healing biodegradable soft materials covalent bonds non-covalent bonds

Construction of multifunctional lanthanum manganese mixed nanoparticles mediated by ionic liquids for selective aerobic oxidation of cyclohexane

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Rare Metals 2024年第5期43卷 2205-2221页

作者： Hao Li Rui-Rui Zhang Ke-Xin Li Shuang Wei yu-mei Liu Rui-Xia Liu Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Selective oxidation of alkanes to produce highvalue chemicals is an essential strategy and means to realize efficient utilization of *** this work,a strategy of lanthanum manganese mixed metal oxides(LMMO)regulated via a facile ionic liquid(IL)-assisted hydrothermal method was proposed to construct the multifunctional catalysts,which exhibited excellent catalytic performance in the selective aerobic oxidation of *** 8.9%cyclohexane conversion with 90%KA oi(cyclohexanol and cyclohexanone)selectivity was achieved over the optimal LMMO catalyst under mild *** effects of anion type,carbon chain length and concentration of ILs on the structure and properties of catalysts were investigated through various characterizations,indicating the structure-directing and template effect of ILs on the multifunctional *** formation of self-assembled spherical nanoparticles followed the"dissolution-nucleation-proliferation"mechanism with the introduction of 1-butyl-3-methylimidazolium hydrogen sulfate,ascribing the synergistic effect between the microenvironment of ILs and the hydrothermal ***,the high reactive oxygen concentration redox capacity,and suitable basic sites of LMMO catalysts mediated by ILs enhance the activation of C-H bonds and molecular oxygen,simultaneously influencing the adsorption and desorption of the substrate.A comprehensive understanding of the high KA oil selectivity and radical reaction mechanism was elucidated based on in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and radical trapping *** recycling and regeneration experiments further illuminated that the removal of adsorbed cyclohexanone acting on the LMMO catalyst was the key to achieve high KA oil selectivity.

关键词： Ionic liquids Nanoparticle Multifunctional catalyst Cyclohexane oxidation